Chlamydia psittaci is an agent that causes ornithosis or psittacosis, which can infect homing and wild birds, mammalian animals and humans. Since this disease is an important zoonosis that is fatal ...and distributed worldwide, it is important to know its occurrence. This study aimed to survey the seropositivity of Chlamydia psittaci in three psittacine collections in three zoos in Portugal. In this study, 112 blood samples of the psittacine belonging to Order Psitaciformes (encompassing 31 species from 14 genera) were used. These samples were tested using a commercial ELISA kit (Immunocomb®, Biogal). The serological examination of psittacine samples using ELISA showed that 54 were positive (48.2%; 95% confidence interval, CI: 39.0-57.4%). The genus Ara exhibited significantly higher seropositivity than other genera (P<0.05). Based on the serological data from this study, we demonstrate that antibodies against Chlamydia psittaci are circulating in the blood of these tested animals. Since psittacosis is a public health concern, zoonotic issues of these results should be considered.
Chlamydia psittaci uzročnik je ornitoze (psitakoze) koja može inficirati i domaće i divlje ptice, sisavce, ali i ljude. S obzirom da je ova bolest sveprisutna zoonoza koja može biti fatalna, a rasprostranjena je diljem svijeta, važno ju je znati prepoznati kada se pojavi. Cilj je ovog rada bio ispitati seropozitivnost na Chlamydia psittaci u tri populacije papiga koje pripadaju trima zoološkim parkovima u Portugalu. U ovoj studiji rabljeno je 112 uzoraka krvi papiga iz reda Psitaciformes (31 različita vrsta iz 14 različitih rodova); uzorci su podvrgnuti komercijalnom ELISA testu (Immunocomb®, Biogal). Serološko ispitivanje uzoraka papiga uporabom ELISA testa pokazalo je da ih je 54 (48,2 %; 95 % interval pouzdanosti, CI: 39,0 %-57,4 %) bilo pozitivno. Rod Ara pokazao je značajno veću seropozitivnost od ostalih rodova (P<0,05). Na temelju seroloških podataka iz ove studije, dokazali smo da protutijela za Chlamydia psittaci cirkuliraju u krvi testiranih životinja. S obzirom da psitakoza predstavlja javnozdravstveni problem, potrebno je razmotriti zoonotska pitanja naših rezultata.
Chlamydia psittaci pneumonia is a relatively rare zoonotic disease. However, lack of specific clinical symptoms, effective and rapid laboratory diagnosis methods and clear epidemiological data ...sometimes may make it difficult to diagnose the disease. This paper reports a case of Chlamydia psittaci pneumonia diagnosed by metagenomic next-generation sequencing (mNGS), suggesting that mNGS technology has high clinical application value in the diagnosis of community-acquired pneumonia with unknown pathogens.
Abstract
Introduction:
The objective of this study was to explore the clinical, laboratory, and imaging features of severe
Chlamydia psittaci
pneumonia in order to improve early diagnosis and ...treatment success rates.
Methods:
We conducted a retrospective record review of 14 cases of severe
Chlamydia psittaci
pneumonia diagnosed by metagenomic next-generation sequencing technology in our hospital. We extracted and analyzed data on the clinical symptoms and signs, contact history, laboratory investigations, chest computed tomography, treatment, and clinical outcomes.
Results:
Of the 14 patients, 12 (86%) were male and two (14%) were female, with a mean age of 57 years (SD: 7 years). Eleven patients (79%) had a history of poultry contact. The main clinical manifestations were fever (n = 14, 100%), flu-like symptoms (n = 10, 71%), cough, sputum (n = 9, 64%), and dyspnea (n = 5, 36%). Blood tests revealed marked elevation of neutrophil percentage, C-reactive protein, procalcitonin, brain natriuretic peptide, and creatine kinase levels; slight elevation of aspartate aminotransferase, creatinine, urea, fibrinogen, and D-dimer levels; and decreased albumin, sodium, and calcium levels. Chest computed tomography showed bilateral lesions (n = 7, 50%), middle-lower lobe lesions (n = 10, 71%), lesions in multiple lobes (n = 9, 64%), consolidation shadows (n = 11, 79%), and pleural effusions (n = 11, 79%). The median time from disease onset to hospital admission was 4.5 days (interquartile range: 1–17 days); the mean length of hospital stay was 20.9 ± 8.5 days, and the mean time from admission to diagnosis was 5.1 ± 2.6 days. After diagnosis, patients were either treated with doxycycline alone or doxycycline combined with quinolones. All 14 patients developed respiratory failure and received invasive mechanical ventilation; two (14%) received veno-venous extracorporeal membrane oxygenation, four (29%) received continuous renal replacement therapy, and three (21%) died.
Discussion and conclusion:
A poultry contact history and typical flu-like symptoms are early indicators of
Chlamydia psittaci
pneumonia. Substantial elevations in procalcitonin, creatine kinase, and brain natriuretic peptide indicate severe disease. Metagenomic next-generation sequencing is useful for diagnosis. Early empirical antibiotic therapy with quinolones can reduce the mortality in critically ill patients.
Introduction
.
Chlamydia psittaci
(
C. psittaci
) is a zoonotic infection, that causes psittacosis (parrot fever) in humans, leading to severe clinical manifestations, including severe pneumonia, ...adult respiratory distress syndrome, and, in rare cases, death.
Gap Statement
. Rapid, sensitive and specific detection of
C. psittaci
facilitates timely diagnosis and treatment of patients.
Aim
. This study aimed to engineer the LAMP-CRISPR/Cas12b platform for
C. psittaci
detection.
Methodology
. The loop-mediated isothermal amplification (LAMP) technique and clustered regularly interspaced short palindromic repeats-CRISPR associated protein 12b (CRISPR-Cas12b) assay were combined to establish two-step and one-tube LAMP-CRISPR/Cas12b reaction systems, respectively, for rapidly detecting
C. psittaci
.
Results
. The two-step and one-tube LAMP-CRISPR/Cas12b assay could complete detection within 1 h. No cross-reactivity was observed from non-
C. psittaci
templates with specific LAMP amplification primers and single-guide RNA (sgRNA) targeting the highly conserved short fragment CPSIT_0429 gene of
C. psittaci
. The detection limits of the two-step and one-tube LAMP-CRISPR/Cas12b reaction were 10
2
aM and 10
3
aM, respectively. The results were consistent with qPCR for nucleic acid detection in 160 clinical samples, including 80 suspected
C. psittaci
samples, kept in the laboratory.
Conclusions
. The LAMP-CRISPR/Cas12b assay developed in this study provides a sensitive and specific method for rapidly detecting
C. psittaci
and offers technical support for its rapid diagnosis.
•Longitudinal study followed pregnant Thoroughbred mares and foals from 14 studs.•C. psittaci equine abortions can occur sporadically every foaling season.•Healthy newborn foals tested positive to C. ...psittaci with no clinical disease.•Abortion cases correlated with ‘avian’ C. psittaci genotype and with frost events.•C. psittaci should be routinely tested for in equine abortion cases.
Late-term foal loss due to the traditional avian pathogen Chlamydia psittaci recently emerged as a threat to the Australian Thoroughbred industry. A longitudinal study of 14 stud farms was undertaken to better understand C. psittaci infection in pregnant mares and their foals by evaluating C. psittaci prevalence, equine herpesvirus-1 (EHV-1) co-infection, avian reservoirs, and potential risk factors. Mucosal swabs taken from 228 healthy pregnant mares and their foals were tested for C. psittaci and EHV-1 using species-specific qPCR assays.
No foal loss was recorded due to either pathogen, and no mare tested positive to either C. psittaci or EHV-1. However, healthy newborn foals tested positive to both pathogens, at low levels, with 13.2% (n = 30/228) and 14.5% (n = 33/228) prevalence for C. psittaci and EHV-1, respectively. Co-infection occurred in 1.3% (n = 3/228) of foals. In avian environmental faecal samples collected from the same studs, C. psittaci was detected at 5.3% (n = 5/94). Multiple logistic regression modelling found that foals born in winter were more likely to be infected with C. psittaci (adjusted odds ratio = 15.83; P < 0.001; Confidence Interval 5.12–48.49). Being a maiden mare, absence of prophylactic vaginal suture, interventions in the last trimester and residing on a farm with prior history of C. psittaci abortion posed no higher risk to infection in the newborn. Analysis of all reported C. psittaci abortion cases (Hunter Valley, 2016–2019) revealed a dominant C. psittaci sequence type (denoted ST24) and a significant correlation with frost events (Spearmans’ rho = 0.44; P = 0.002).
ABSTRACT
Chlamydia psittaci
is a human pathogen that causes atypical pneumonia after zoonotic transmission. We confirmed that
C. psittaci
infection induces oxidative stress in human bronchial ...epithelial (HBEs) cells and explored how this is regulated through miR-184 and the Wnt/β-catenin signaling pathway. miR-184 mimic, miR-184 inhibitor, FOXO1 siRNA, or negative control sequence was transfected into HBE cells cultured in serum-free medium using Lipofectamine 2000. Then, prior to the cells were infected with
C. psittaci
6BC, and the cells were treated with or without 30 µM Wnt/β-catenin inhibitor ICG-001. Quantification of reactive oxygen species, malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione was carried out according to the manufacturer’s protocol using a corresponding assay kit. The outcome of both protein and gene was measured by western blotting or real-time fluorescence quantitative PCR. In
C. psittaci
-infected HBE cells, miR-184 was upregulated, while one of its target genes,
FOXO1
, was downregulated. ROS and MDA levels increased, while SOD and GSH contents decreased after
C. psittaci
infection. When miR-184 expression was downregulated, the level of oxidative stress caused by
C. psittaci
infection was reduced, and the Wnt/β-catenin signaling pathway was inhibited. The opposite results were seen when miR-184 mimic was used. Transfecting with FOXO1 siRNA reversed the effect of miR-184 inhibitor. Moreover, when the Wnt/β-catenin-specific inhibitor ICG-001 was used, the level of oxidative stress induced by
C. psittaci
infection was significantly suppressed. miR-184 can target FOXO1 to promote oxidative stress in HBE cells following
C. psittaci
infection by activation of the Wnt/β-catenin signaling pathway.
Abstract
We describe 4 cases of Chlamydia psittaci pneumonia among medical staff in a coronavirus disease 2019 (COVID-19) screening ward, as well as the experience of dealing with this nosocomial ...infection event. Atypical pneumonia, in addition to COVID-19, should be considered when clustering cases occur, even during a COVID-19 pneumonia pandemic.
Although the protective effects of Chlamydia psittaci plasmid-encoded protein CPSIT_P7 as vaccine antigens to against chlamydial infection have been confirmed in our previous study, the function and ...mechanism of CPSIT_P7 inducing innate immunity in the antibacterial response remain unknown. Here, we found that plasmid protein CPSIT_P7 could induce M1 macrophage polarization upregulating the genes of the surface molecule CD86, proinflammatory cytokines (TNF-α, IL-6, and IL-1β), and antibacterial effector NO synthase 2 (iNOS). During M1 macrophage polarization, macrophages acquire phagocytic and microbicidal competence, which promotes the host antibacterial response. As we observed that CPSIT_P7-induced M1 macrophages could partially reduce the infected mice pulmonary Chlamydia psittaci load. Furthermore, CPSIT_P7 induced M1 macrophage polarization through the TLR4-mediated MAPK and NF-κB pathways. Collectively, our results highlight the effect of CPSIT_P7 on macrophage polarization and provide new insights into new prevention and treatment strategies for chlamydial infection.
•Chlamydia psittaci plasmid-encoded CPSIT P7 induced M1 macrophage polarization in vitro and in vivo thereby eliciting antimicrobial responses.•CPSIT_P7 induced M1 macrophage polarization through the TLR4-mediated MAPK and NF-κB pathways.•New insights about the mechanism by which CPSIT_P7-induced M1 macrophage plays a role in host innate immune against Chlamydia psittaci infection.
Ocular adnexal marginal zone B-cell lymphomas (OAMZLs) arise in the connective tissues of the orbit or in the mucosa-associated lymphoid tissue of the conjunctiva. Here, we present the immunological ...and genetic analyses of 20 primary Chlamydia psittaci (Cp)-negative OAMZLs. Analysis of the immunoglobulin variable heavy chain (IgV sub(H)) gene usage demonstrated a significant preference for V sub(H)4-34. A combined analysis across all previously published OAMZLs confirmed that this is a general feature of OAMZL, in particular of the Cp-negative group. Our series of OAMZLs did not express the characteristic rheumatoid factor V sub(H)DJ sub(H) rearrangements that were previously found in salivary gland- and gastric-marginal zone B-cell lymphomas (MZBCLs). We did not detect the MZBCL-specific chromosomal translocations, t(11; 18) API2-MALT1 (mucosa-associated lymphoid tissue1) and t(14; 18) IgH/MALT1. Two cases contained a premature stop codon in the A20 gene (TNFAIP3) and one case harbored the activating MYD88 hotspot mutation L265P. Variable nuclear expression of BCL10, NF Kappa B1 (p50) and NF Kappa B2 (p52) suggests that other additional genetic abnormalities affecting the NF Kappa B pathway exist within this group of lymphomas. OAMZL showed variable expression of the chemokine receptor CXCR3 and integrin alpha 4 beta 7 by the tumor B cells, and low interferon- gamma and interlukin-4 mRNA levels in the tissue, indicative of an inflammatory environment with features in between those previously found in cutaneous and other extranodal MZBCL. The strongly biased usage of V sub(H)4-34 in Cp-negative OAMZLs suggests involvement of a particular stimulatory (auto-) antigen in their development.
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